As the LED display technology continues to develop, while people are pursuing high-definition picture quality and high-accuracy color reproduction, various functions such as gaming, entertainment, network movies and music, or human-computer interaction have been increasingly integrated into the LED display devices, and the LED displays are also having increasingly larger sizes. And in some audio-visual education domains, big LED displays are gradually replacing the traditional blackboard way of teaching.
A typical large-sized display, especially one for use in audio-visual education having prominent human-computer interaction requirement, may usually be equipped with various intelligent multimedia human-machine interaction modules such as a microcomputer module, a backlight drive module, a power amplifier module, and a motherboard module. As the increasingly larger sized LED displays have been posing still higher requirements on their driving capability, to ensure the normal operation of these modules, in the prior art usually several separate power modules may be provided in the same device to convert the input AC power respectively thereby satisfying the power requirements. For example, a separate adapter may be equipped for the microcomputer, a constant-voltage power supply may be provided for the motherboard and the power amplifier module, and a constant-current module may be configured for the backlight module, the constant-current module deriving a voltage from the current-voltage power supply. However, because there are employed multiple power supply modules, and the adapter, the constant-voltage power supply, and the constant-current backlight drive module each uses an independent control circuit and rectifier/filter circuit, the resulting circuitry are complex.